Has anyone ever upgraded their ring before their big day?

Hi, I’ve been engaged to my fiancé for almost 2 years. Got engaged 3 months into the relationship (known each other since school)  He always joked about asking me and I brushed it off until he actually did ask – on my son’s birthday! I was obviously over the moon. It was love at first sight from our first date. (Lost touch for a couple of years). The thing that’s bugging me is the ring… I thought I could learn to love it as my fiancé chose it and they aren’t cheap and I don’t want to sound ungrateful or anything but it really isn’t what I envisioned what my ring would be like when the time came to be asked that question, in fact I think I only wear it because I don’t want to hurt his feelings – I sound horrible I know I do. I like the band and the fact it’s white gold but that’s it. Everything else – not so much. This is so I can blurt it out more than anything. I know engagement rings cost a lot of money generally but I kind of wish he had asked me beforehand what kind of style I liked. It’s too late to change it at the shop – been on my finger 2 years. Don’t get married until 2018. Has anyone ever upgraded their ring before their big day? Please don’t judge and please don’t be too negative towards me, I’m giving myself a hard time as it is. Just need advice and some kind words. Thank you.